This is a simple problem, best illustrated by example. Note that unlike strike, plunge has a unique direction. A plane striking 058 is the same as one striking 238, but a line trending 058 is not the same as one trending 238. Trend is the direction down the plunge of the line.
+-----------------------------+ +-----------------------------+ |1 x 900 | |2 \ | | \ | | \ | | \ | | \ | | \ | | \ | | \ | | \ | | x 1000 | | \ | | | \ | | \ | | | \ | | \ | | | \ | | \ | | | \ | | \328| | | \ 1100 | | \ | | | x | | \ | | | CONTOUR INTERVAL = 100 M | | \| | | | | \ | | 0 100 200 M | | 0 100 200 M \ | | |----I----| SCALE | | |----I----| SCALE | +-----------------------------+ +-----------------------------+ 1. Find the trend and plunge 2. The trend is merely the of the borehole shown. azimuth of the map trace +-----------------------------+ +-----------------------------+ |3 | |4 x 900 m | | | | \ | | | | \ | | |-----------|-----------| | | \ | | o + | | | | \ | | 23 + | | | | x 1000 | | +-----------+ | | \ | | + | | | Trend = 328 \ | | + | | | Plunge = 23 \ | | + | | \ | | | | \ | | Tan P = 100/240 = 0.416 | | x 1100 | | P = 22.6 | | \ | | | | \ | | 0 100 200 M | | 0 100 200 M \ | | |----I----| SCALE | | |----I----| SCALE | +-----------------------------+ +-----------------------------+ 3. Determine spacing of elevation 4. Final result points using a cross-section or trigonometry.
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